Intrinsic Circuit Organization and Theta–Gamma Oscillation Dynamics in the Entorhinal Cortex of the Rat
TLDR
It is found that EC5 and EC2 principal neurons form large axonal networks mainly within their layers, interconnected by the more vertically organized axon trees of EC3 pyramidal cells, which may underlie their behaviorally distinct firing patterns in the waking animal.Abstract:
A thorough knowledge of the intrinsic circuit properties of the entorhinal cortex (EC) and the temporal dynamics these circuits support is essential for understanding how information is exchanged between the hippocampus and neocortex. Using intracellular and extracellular recordings in the anesthetized rat and anatomical reconstruction of single cells, we found that EC5 and EC2 principal neurons form large axonal networks mainly within their layers, interconnected by the more vertically organized axon trees of EC3 pyramidal cells. Principal cells showed layer-specific unique membrane properties and contributed differentially to theta and gamma oscillations. EC2 principal cells were most strongly phase modulated by EC theta. The multiple gamma oscillators, present in the various EC layers, were temporally coordinated by the phase of theta waves. Putative interneurons in all EC layers fired relatively synchronously within the theta cycle, coinciding with the maximum power of gamma oscillation. The special wiring architecture and unique membrane properties of EC neurons may underlie their behaviorally distinct firing patterns in the waking animal.read more
Citations
More filters
Journal ArticleDOI
The origin of extracellular fields and currents — EEG, ECoG, LFP and spikes
TL;DR: High-density recordings of field activity in animals and subdural grid recordings in humans can provide insight into the cooperative behaviour of neurons, their average synaptic input and their spiking output, and can increase the understanding of how these processes contribute to the extracellular signal.
Journal ArticleDOI
Mechanisms of Gamma Oscillations
György Buzsáki,Xiao Jing Wang +1 more
TL;DR: The cellular and synaptic mechanisms underlying gamma oscillations are reviewed and empirical questions and controversial conceptual issues are outlined, finding that gamma-band rhythmogenesis is inextricably tied to perisomatic inhibition.
Journal ArticleDOI
Cross-Frequency Phase–Phase Coupling between Theta and Gamma Oscillations in the Hippocampus
TL;DR: It is suggested that cross-frequency phase coupling can support multiple time-scale control of neuronal spikes within and across structures.
Journal ArticleDOI
Brain rhythms and neural syntax: implications for efficient coding of cognitive content and neuropsychiatric disease.
György Buzsáki,Brendon O. Watson +1 more
TL;DR: Findings from animal studies showing that most forms of brain rhythms are inhibition-based are reviewed, producing rhythmic volleys of inhibitory inputs to principal cell populations, thereby providing alternating temporal windows of relatively reduced and enhanced excitability in neuronal networks.
Journal ArticleDOI
Recurrent inhibitory circuitry as a mechanism for grid formation
Jonathan J. Couey,Aree Witoelar,Sheng-Jia Zhang,Kang Zheng,Jing Ye,Benjamin Dunn,Rafal Czajkowski,May-Britt Moser,Edvard I. Moser,Yasser Roudi,Menno P. Witter +10 more
TL;DR: It is demonstrated that stellate cells, the principal cell type in the layer II grid network, are mainly interconnected via inhibitory interneurons, and that stable grid firing can emerge from a simple recurrent inhibitory network.
References
More filters
Journal ArticleDOI
Microstructure of a spatial map in the entorhinal cortex
TL;DR: The dorsocaudal medial entorhinal cortex (dMEC) contains a directionally oriented, topographically organized neural map of the spatial environment, whose key unit is the ‘grid cell’, which is activated whenever the animal's position coincides with any vertex of a regular grid of equilateral triangles spanning the surface of the environment.
Journal ArticleDOI
High gamma power is phase-locked to theta oscillations in human neocortex.
Ryan T. Canolty,Erik Edwards,Erik Edwards,Sarang S. Dalal,Maryam Soltani,Maryam Soltani,Srikantan S. Nagarajan,Heidi E. Kirsch,Mitchel S. Berger,Nicholas M. Barbaro,Robert T. Knight +10 more
TL;DR: The results indicate that transient coupling between low- and high-frequency brain rhythms coordinates activity in distributed cortical areas, providing a mechanism for effective communication during cognitive processing in humans.
Book
Statistical Analysis of Circular Data
TL;DR: This book presents a meta-modelling framework for analysing two or more samples of unimodal data from von Mises distributions, and some modern Statistical Techniques for Testing and Estimation used in this study.
Journal ArticleDOI
The three-dimensional organization of the hippocampal formation: a review of anatomical data.
David G. Amaral,Menno P. Witter +1 more
TL;DR: It is concluded that it is heuristically most reasonable to consider the hippocampal formation as a three-dimensional cortical region with important information processing taking place in both the transverse and long axes.
Journal ArticleDOI
Memory systems of the brain: A brief history and current perspective
TL;DR: This article traces the development of these ideas that memory is composed of multiple separate systems supported by the hippocampus and related structures, the amygdala, the neostriatum, and the cerebellum and provides a current perspective on how these brain systems operate to support behavior.